1. Das EFXDas EFX made such a profound impact in 1992 with its debut album, Dead Serious,and early hits like “They Want EFX”that audiences could be forgiven for imagining that the future of hip-hop resided in dreadlocked MCs spitting tongue-twisting, borderline-nonsensical, pop-culture-infused rhymes at a machine-gun clip, à la Das EFX’s Krazy Drayzy and Skoob. The duo’s homemade wordplay, ubiquitous use of nonsense phrases like “iggedy,” and lyrical dexterity looked for a short while like a revolutionary new movement in hip-hop, as acts like Fu-Schnickens and even a young, pre-Reasonable DoubtJay-Z“borrowed” Das EFX’s radical new style. It was not to be, however; though Das EFX scored another gold album with 1993’s Straight Up Sewaside, it ultimately proved to be a faddish dead end.

2. Arrested DevelopmentCritics couldn’t heap accolades upon Arrested Development quickly enough when the group released 3 Years, 5 Months & 2 Days In The Life Of… in spring 1992. “What distinguishes Arrested Development from other rap groups is their positive, family-oriented themes, a welcome departure from the misogynistic and violent lyrics of hard-core rap acts,” went a typically hyperbolic feature on the group in Ebony. Arrested Development did stand out, though. There were eight members (including 60-year-old “spiritual adviser” Baba Oje), usually decked out in dashikis or other African garb, and the group’s musical style was heavily informed by its social consciousness. Frontman Speech labeled it “conscious hip-hop,” meaning “trying to be aware of what we can change.” Even though hip-hop always offered alternatives, gangsta rap had a habit of dominating the media, so 3 Years offered a positive, unthreatening alternative for people who didn’t know about 3 Feet High And Rising or The Low End Theory. 3 Years became the first major hit of the alternative hip-hop era, selling 4 million copies, earning two Grammys and an MTV Video Music Award, and placing second in Spin’s year-end list, just below Pavement’s Slanted And Enchanted and above Beastie Boys’ Check Your Head. Although Arrested Development had another hit in 1993 with its Unplugged album, the comedown didn’t take long. The massive success of Dr. Dre’s The Chronic, released in December ’92, basically ended America’s brief love affair with conscious hip-hop and launched the career of Snoop Doggy Dogg. Arrested Development’s awkwardly titled second album, Zingalamaduni—Swahili for “a beehive of culture”—sold poorly, and the group disbanded two years later, though it’s since reunited.

3. Digable PlanetsBrooklyn trio Digable Planets didn’t start the hip-hop jazz revolution, but the group’s 1993 debut, Reachin’ (A New Refutation Of Time And Space), captured the sound at its most pervasive. Jazz samples provided the album’s foundation, and the intellectual, bohemian style of members Butterfly, Doodlebug, and Ladybug Mecca gave Digable Planets an effortless cool. The album drew loads of critical adulation and earned gold status thanks to the hit “Rebirth Of Slick (Cool Like Dat),” which also nabbed a Grammy for Best Rap Performance. But Dig Plan fell prey to the “commercial success followed by difficult second album” curse with 1994’s Blowout Comb, which stripped down its sound and embraced an aggressive black-nationalist message. A Reachin’ retread probably wouldn’t have fared any better; by 1994, gangsta rap was completely dominating the mainstream, and the release of The Notorious B.I.G.’s Ready To Die a month before Blowout Comb only reinforced that. Like Arrested Development, Digable Planets broke up by 1996.

4. Disposable Heroes Of HiphoprisyThe early ’90s were the glory days of so-called “conscious rap,” a time of boundless optimism and dizzying media hyperbole: “The Disposable Heroes Of Hiphoprisy have single-handedly enlarged the vision of rap while also expanding the music’s vocabulary of social criticism,” read the Rolling Stone review of the group’s first and only album, 1992’s Hypocrisy Is The Greatest Luxury. Where the posi-rap of Arrested Development and laid-back jazz of Digable Planets skewed sunny, The Disposable Heroes favored darkness, via an industrial-tinged sound and ominous song titles like “Television, The Drug Of The Nation” and “Everyday Life Has Become A Health Risk.” (And just in case anyone missed the point, the album featured a cover of the Dead Kennedys’ “California Über Alles.”) Although the group had some critics fawning, it had too many strikes against it for wider popularity: Its harder sound was less accessible, its message seemingly took precedence over songwriting, and frontman Michael Franti simply wasn’t much of a rapper. (Check out the stilted statistic-reading and painfully obvious lyrics that make up “Television, The Drug Of The Nation.”) In their hip-hop compendium That’s The Joint!, authors Murray Forman and Mark Anthony Neal note that Disposable Heroes and similar conscious acts “failed to grasp the significance of producing music that would be considered danceable by the black masses they aimed to attract.” They may have a point; Franti had a huge hit when he lightened up in 2008 on Spearhead’s ultra-poppy “Say Hey (I Love You).” He followed it up with an album called The Sound Of Sunshine.

5. P.M. DawnKRS-One famously bum-rushed a P.M. Dawn show after the duo’s frontman Prince Be asked of the rap legend in an interview with Details, “KRS-One wants to be a teacher, but a teacher of what?” KRS-One needn’t have worried about P.M. Dawn’s lasting influence on hip-hop, however. Like many of the acts here, P.M. Dawn was a meteorite, not a planet; it burned brightly, then died. The duo shook up hip-hop with a radically different aesthetic: Prince Be took De La Soul’s quickly discarded “D.A.I.S.Y. Age” vibe to new heights of hippified mellowness, dressing like he was perennially headed to Woodstock, performing a duet with Boy George on the group’s second album, and titling its fourth album Dearest Christian, I’m So Very Sorry For Bringing You Here. Love, Dad. In other words, he did everything in his power to push P.M. Dawn to the very fringes of the pop and hip-hop world and ensure that no one followed in the group’s nakedly sincere, psychedelic, overtly Christian path. In recent years, Prince Be has had a lot more to worry about than falling out of fashion with hip-hop fans: He’s has had two strokes, one of which led to the partial amputation of a gangrene-infected leg, though he still managed to release this year’s desperate-sounding Greatest Hits Live!

6. Blood Of AbrahamAs entrepreneurs and artists, Jews have played a large role in hip-hop’s development, but their religion tends not to play too central a role in their music. (An exception would be Scott Storch, who named his publishing company Tuff Jew Productions). That certainly isn’t the case with Blood Of Abraham, Orthodox Jewish Eazy-E protégés who made their uncompromising faith a central part of their image and music on their Ruthless 1993 debut, Future Profits. The duo even collaborated with the N.W.A. legend, and bizarrely enough, a young Will.I.Am (then Will-1X) on the explosively titled track, “Niggaz And Jewz (Some Say Kikes).” Alas, it turns out the world wasn’t ready for Hasids Wit Attitude, and the album proved a commercial failure. The two performers reinvented themselves as dazzlingly musical, post-apocalyptic storytellers on the 2000 concept album Eyedollartree, but when label Atomic Pop folded, the disc went into limbo and didn’t receive a proper release until 2005.

7. Me Phi MeAs gangsta rap continued to upset delicate sensibilities in the early ’90s, La-Ron K. Wilburn, better known as Me Phi Me, offered a comforting antidote. Pegged as a savior of hip-hop uniquely qualified to elevate the genre to some new plateau of respectability, he debuted in 1992 with ONE, landing a tour with fellow feel-gooders Arrested Development and inclusion on the soundtrack to Reality Bites alongside Squeeze and Lisa Loeb. It wound up being a dubiously perfect fit. With a handle that sounded deliberately collegiate, and folk-guitar-flecked songs like “Sad New Day,” the Mohawk-dreadlocked Wilburn gently rapped about fulfilling one’s potential, using one’s mind, and practicing the meditative art of unwinding. In fact, Wilburn’s attitude was so positive and uplifting, he positively uplifted himself out of hip-hop and into a career as a corporate consultant.

8. Count Bass DLive instrumentation didn’t play much of a role on hip-hop albums when the spectacularly talented Count Bass D released Pre-Life Crisis in 1995, so the album’s jazzy, organic sound, dominated by Count Bass D’s piano, took listeners by surprise and helped make him a critical darling. The Nashville rapper’s lyrics were just as unexpected: Instead of the usual braggadocio, Bass D filled his album with stream-of-consciousness weirdness about ChapStick and meeting T-Boz from TLC. The good Count was dropped by his label in 1996 and has subsequently reinvented himself as a sample-heavy underground eccentric affiliated with MF Doom, with whom he recorded “Potholderz.” Even Count Bass D hasn’t shown any interest in pursuing the potentially revolutionary sound and style of his debut.

9. Lady SovereignAlthough popular in its native United Kingdom, the hip-hop subgenre of grime never made much of an impact Stateside, probably because American ears couldn’t parse rapid-fire rapping delivered via thick English accents. Lady Sovereign wasn’t the only grime artist who failed to catch on—Dizzee Rascal was also poised for big things here—but no one else had Lady Sovereign’s novelty or a Jay-Z endorsement. Hova signed the self-proclaimed “biggest midget in the game” to Island Def Jam on the strength of her UK singles, and her 2005 EP, Vertically Challenged, produced a minor hit with “Random.” Sov’s debut full-length, Public Warning, wouldn’t arrive until almost a year later, though it produced a hit with “Love Me Or Hate Me” and earned her a spot opening for Gwen Stefani in 2007. Burned out after touring, Sovereign moved in with her father and basically disappeared. After Def Jam dropped her, her move into a poppier direction on 2009’s Jigsaw met with apathy from listeners. Most recently, she did time on reality TV on Celebrity Big Brother in the UK, though didn’t do any better there: She was the third one evicted from the house.

10. Bubba SparxxxTimbaland and protégé Bubba Sparxxx had an audacious, unique vision for Deliverance, Sparxxx’s follow-up to his major-label debut Dark Days, Bright Nights: fusing bluegrass and socially conscious hip-hop to create a whole new subgenre with deep roots in the red clay of the Dirty South. To that end, the album combined freaky Timbaland drum patterns with the playing of the Yonder Mountain String Band and Area Code 615 in a way that made bluegrass and hip-hop fans sit up and say, “Huh?” followed by “Wha?” and ultimately “Meh.” Sparxxx left Timbaland’s Beat Club label and released another winner in 2006, The Charm.But fiddles and steel guitar were conspicuously absent on the disc, and its hit single, “Ms. New Booty,” could never be accused of trying anything revolutionary, or even particularly different.

11. Panjabi MCPanjabi MC’s remix of “Beware Of The Boys (Mundian To Bach Ke)” offered a unique form of cross-cultural communication: the Bhangra anthem was built on a maddeningly infectious sample of the Knight Rider theme song and boasted an unusually political guest rap from Jay-Z, who doesn’t dole out guest appearances liberally. The result felt both soothingly, reassuringly familiar (is there anything more sacred to Americans than cheesy ’80s television theme songs?) and intriguingly exotic. Alas, Panjabi MC never did cross over to the United States market, though the musician/producer’s work has popped up in places as random as Queer As Folk, Bend It Like Beckham, Wild Boyz,and WWE The Music Volume 9, so that’s gotta be worth something, right?

12. Asher RothYet another big thing that wasn’t, Asher Roth co-opted the melody from Weezer’s “Say It Ain’t So” for his breakout semi-hit “I Love College.” With visions of the next Eminem dancing in its head, Universal signed the feel-good slacker twentysomething MC. But his debut, Asleep In The Bread Aisle,underperformed commercially, thereby sparing the hip-hop world more campy, tongue-in-cheek odes to college decadence and references to Saved By The Bell actress Lark Voorhies delivered in a style that could charitably be described as casual, and less charitably be damned as “amateurish.” Roth has a follow-up planned for next year, but hopefully the sleepy reception for Asleep In the Bread Aisle (which was totes released on 4/20, wink, wink!) will discourage further lyrically challenged college MCs from foisting their work on an unsuspecting public.

13. OnyxLike many of the acts here, Onyx released a debut, 1993’s Bacdafucup, that inspired the kind of explosive response among hip-hop heads that’s difficult, if not impossible, to sustain. Protégés of Run-DMC’s Jam Master Jay, Onyx married the growling, violent aggression of gangsta rap with the energy, attitude, and mosh pits of grunge. It was an explosive (and, for a brief period, tremendously lucrative) combination, but it didn’t lead to anything substantial, either for Onyx or for hip-hop as a whole. Onyx continued to release albums throughout the ’90s, but its cartoonish blend of headbanging and thug swagger never sparked a movement. Moshing has failed to join encouraging audiences to put their hands in the air and giving it up for their city as staples of hip-hop concerts, and Onyx rappers Sticky Fingaz and Fredro Starr switched their focus to acting as Onyx’s commercial fortunes faded.

14. MC 900 Ft. JesusReleased in 1989, Mark Griffins’ debut as MC 900 Ft. Jesus, Hell With The Lid Off, resonated more with the industrial nation than with the hip-hop scene. But as it turned out, Griffin really didn’t fit in anywhere. Dark, alienated, starkly digital, and unafraid to deconstruct samples into their least recognizable essences, Griffin followed up Hell with 1991’s Welcome To My Dream and 1994’s One Step Ahead Of The Spider, two more albums of brilliant but confounding beats and rhymes. They failed to break into the mainstream, after which Griffin aborted work on a fourth full-length and faded into history. A critical darling lauded by some as the possible future of hip-hop, Griffin turned out to be just another delirious, divinely inspired fringe-dweller.

15. Buck 65Considering how little Buck 65’s name gets bandied about today, in hip-hop circles and elsewhere, it can be easy to forget what an explosive impact the This Right Here Is Buck 65 compilation made in early 2005. The Canadian rapper-singer-songwriter was hailed as hip-hop’s next bold evolutionary step forward for his genre-mashing collision of hip-hop, talking blues, gothic country, surrealistic imagery, and art-school pretension. Buck 65 was supposed to be the David Lynch of hip-hop, a singular weirdo following a crazed muse wherever it led. But all the press and critical hosannas didn’t lead to much commercial success. Buck 65’s career didn’t blow up so much as slowly fade away.